The long-lost biological father of Jeff Bezos only learned his son was the billionaire CEO of one of the world’s most successful companies when Bezos’ biographer tracked the man down in late 2012 at the Arizona bike shop he owns.

In an excerpt from his new book “The Everything Store: Jeff Bezos and the Age of Amazon,” a history of the retailer Amazon and its notoriously brilliant and mercurial CEO, Brad Stone writes of how he found Ted Jorgensen, the man who abandoned Bezos and the boy’s mother decades ago. The last time Jorgensen saw his son the boy was three years old.

“’Your son is one of the most successful men on the planet,’ I told him,” Stone writes. “I showed him some Internet photographs on my smartphone , and for the first time in 45 years, Jorgensen saw his biological son. His eyes filled with sorrow and disbelief.”

Jorgensen was a hard-drinking 18-year-old circus performer when he married Bezos’ then 16-year-old mother. Jorgensen couldn’t hold down a job and dropped out of school and the marriage quickly fell apart. The mother remarried and made Jorgensen promise to stay out of the family’s life forever. He did.

Stone writes that Jorgensen seems ashamed that he agreed to stay out of his life all those years ago. “I wasn’t a good father or a husband,” he said. “It was really all my fault.”

Bezos, 49, lives in Seattle, Washington and is worth $27.2 billion today. He’s ranked by Forbes as the 19th richest person on the planet. Bezos did not grant an interview to Stone for the book.